There are 2 versions, mine and Kagemaru's.

For mine, Sage mode is his final smash. Then in sage mode, his final smash is Rasenshuriken.

In Sage mode, Press down taunt or side taunt to activate chakra mode. 

In chakra mode, his final smash is Planetary Rasengan.

In alternate version, 

Just press down to activate sage mode without getting final smash. But the final smashes are still the same as V1.

